In a pristine West Coast alpine environment, there is a 20 square kilometre snowfield feeding a 12 kilometre-long glacier that is bathed in blue ice and dotted with deep crevasses masking a sub-glacier channel of pure glacial melt-water. These extraordinary sights are encountered on Franz Josef Glacier.

Franz Josef Glacier is photographed, admired and traversed by thousands of visitors every year.

The glacier is also always changing; rapidly and dramatically. Fox and Franz Josef Glaciers are some of the fastest moving glaciers around. Whilst most glaciers will move at an average speed of around one metre per day, when at its swiftest, Franz Josef Glacier has been known to move at seven metres per day. Most of the time the main icefall of Franz Josef Glacier will move at around four to five metres per day. Due to the huge amounts of snowfall the head-basin receives and their steep, narrow structure these glaciers are fast movers.

For those who guide this glacier every day, there are many things that make this glacier extraordinary. The team at Franz Josef Glacier Guides face a new landscape every time they take a hiking trip onto the glacier. They must expect that changes will occur rapidly.

And right now on Franz Josef Glacier there is an incredible change occurring before our eyes. A change that has meant that guides can no longer access the glacier by foot, because a section of it is currently deemed too unstable.

In 2004 Franz Josef Glacier developed a depression about 2.3 kilometres up the glacier. At the time, the glacier was in a period of advance and the depression did not have a chance to develop greatly in size. From 2008 the glacier was in a period of thinning and slowing which allowed the depression to develop dramatically, and continued to develop in 2011/12. On January 16th 2012, the ice in the depression thinned to the point where some of the ice from the base of the glacier collapsed into the sub glacier channel, greatly reducing the thickness of the ice. The team at Franz Josef Glacier Guides had been monitoring all of this for many years. But it was still a remarkable turn of events. Many key glaciologists began studying the behaviour of the glacier. It is not often that we get to see something like this happening, so all those with an interest in glaciology were amazed by the developments.

But it was deemed too uncertain for guiding trips to be anywhere near thinning ice. So the team at Franz Josef Glacier Guides brought in the helicopters. And now, for not much more than their original hiking trip prices, guests get to experience a truly spectacular helicopter flight onto the glacier before their hiking trip begins. From the helicopter you get to see that incredible head basin snow field, that breath-taking size of this glacier and the striking alpine setting of the Southern Alps.

While the Franz Josef Glacier Guides and the glaciologists continue to observe the incredible changes happening on the glacier, their guests get to reap the benefits of a truly breath-taking way of accessing the glacier. From the amount of blogs, reviews and youtube postings that guests have been posting about the new Ice Explorer helicopter trip, it seems people are bursting to share their amazing experiences.

And for now, we will all watch and observe the incredible hand of Mother Nature at work.